Was John W. Brooker Co., CPAs hit by ransomware?

John W. Brooker Co., CPAs was listed by the Cicada3301 ransomware operation (United States), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the Cicada3301 ransomware group?

Cicada3301 is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the John W. Brooker Co., CPAs breach?

Cicada3301 published data attributed to John W. Brooker Co., CPAs. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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John W. Brooker Co., CPAs

Claimed by Cicada3301 · listed 2 years ago

21m

Age

since listed · data leaked

Status timeline

ListedSep 24, 2024
Data leakeddate unknown

At a glance

Group: Cicada3301
Status: Data leaked
Country: United States
Sector: Financial
Listed on leak site: Sep 24, 2024

About the victim

AI dossier — public-source company profile

John W. Brooker & Co., CPAs is a professional accounting firm established 42 years ago (circa 1982) specializing in integrated financial services for medical, dental, and other service professionals. They offer financial statements, tax planning, business consulting, financial planning, wealth management, and pension design and administration.

Industry: Accounting & Tax Services
Founded: 1982

Attack summary

Severity: high — Confirmed exfiltration and publication of data from a CPA firm handling sensitive client financial information, tax records, and pension administration. This represents a significant breach of regulated financial and tax data affecting multiple professional clients.

Cicada3301 claims to have exfiltrated data from John W. Brooker & Co., CPAs and published it. The group has posted a download link to the leaked data on their onion site, but specific details about what data categories were compromised are not explicitly stated in the post.

high

Data the group says was taken

AI dossier — extracted from the leak post

Client financial records
Tax planning documents
Business consulting files
Pension plan administration records
Wealth management client data

What the group claims

Financial success is best achieved when the financial advisors know your business, your goals, and you personally. Planning with a team is much more coordinated than planning by a list of contacts. For 42 years, John W. Brooker & Co., CPAs has been providing integrated services to medical and dental professionals, as well as other service professionals. We like to say we are a one-stop shopping for financial statements, tax planning, business consulting, financial planning, wealth management, and pension design and administration. Our clients love the efficiency and personal attention that comes from having their advisors knowledgeable about their profession and financial goals. Downloads: http://cicadacnft7gcgnveb7wjm6pjpjcjcsugogmlrat7u7pcel3iwb7bhyd.onion/john_brooker-dataleak

Sources

Victim sitebrooker-cpa.com
Leak posthttp://cicadabv7vicyvgz5khl7v2x5yygcgow7ryy6yppwmxii4eoobdaztqd.onion/yxe8jwlez5v4i7nd7am98wo2mu3951vm

Source

Indexed 2 years ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About Cicada3301

Cicada3301 is a recently emerged ransomware group that began operations in June 2024, primarily motivated by financial gain through extortion activities targeting organizations across multiple sectors. The group's origin and affiliations remain largely undocumented in public threat intelligence reporting, with limited information available regarding their operational structure or potential connections to other cybercriminal organizations. Based on observed targeting patterns, Cicada3301 has demonstrated a preference for attacking business services, technology, manufacturing, and financial sector organizations, with their operations concentrated primarily in English-speaking countries including the United States, United Kingdom, and Canada, as well as extending to Spain and Singapore. The group has successfully compromised approximately 75 known victims since their emergence, though specific details regarding their attack methodologies, initial access vectors, encryption techniques, and extortion tactics have not been extensively documented in publicly available threat intelligence reports from major cybersecurity firms or government agencies. Given the limited public documentation available from CISA, FBI, Mandiant, or other reputable security researchers, the group's current operational status, technical capabilities, and specific attack infrastructure remain largely uncharacterized in open-source intelligence reporting. As of the most recent observations, Cicada3301 appears to remain active in conducting ransomware operations, though comprehensive analysis of their tactics, techniques, and procedures awaits more detailed public reporting from established threat intelligence sources. The group has been linked to 75 public disclosures across our corpus. First observed on a leak site on June 20, 2024; most recent post September 4, 2025. The operation is currently inactive.

Timeline of this disclosure

September 24, 2024John W. Brooker Co., CPAs listed by Cicada3301on the group's public leak site

Other recent disclosures by Cicada3301

Cicada3301 has been linked to 75 public victims on Darkfield. A sample of the most recent:

See the full Cicada3301 dossier →

Sector and geography

This disclosure adds to ransomware activity in the Financial sector, which has 426 disclosures indexed across all operators we track. Geographically, John W. Brooker Co., CPAs is reported in United States, a country with 11,033 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Cicada3301 means John W. Brooker Co., CPAs appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Report the incident to your national CERT, CISA (United States), as required for your jurisdiction.
Monitor for the data appearing on Cicada3301's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.